/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB

	This library is free software; you can redistribute it and/or
	modify it under the terms of the GNU Library General Public
	License as published by the Free Software Foundation; either
	version 2 of the License, or (at your option) any later version.

	This library is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	Library General Public License for more details.

	You should have received a copy of the GNU Library General Public
	License along with this library; if not, write to the Free
	Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
	MA 02111-1307, USA */

/* Parser needs these defines always, even if USE_RAID is not defined */
#define RAID_TYPE_0 1	/* Striping */
#define RAID_TYPE_x 2	/* Some new modes */
#define RAID_TYPE_y 3

#define RAID_DEFAULT_CHUNKS 4
#define RAID_DEFAULT_CHUNKSIZE 256*1024 /* 256kB */

extern const char *raid_type_string[];

#ifdef __cplusplus
extern "C" {
#endif
const char *my_raid_type(int raid_type);
#ifdef __cplusplus
}
#endif

#if defined(USE_RAID) && !defined(DONT_USE_RAID)

#ifdef __GNUC__
#pragma interface			/* gcc class implementation */
#endif
#include "my_dir.h"

/* Trap all occurences of my_...() in source and use our wrapper around this function */

#ifdef MAP_TO_USE_RAID
#define my_read(A,B,C,D)		my_raid_read(A,B,C,D)
#define my_write(A,B,C,D)		my_raid_write(A,B,C,D)
#define my_pwrite(A,B,C,D,E)	my_raid_pwrite(A,B,C,D,E)
#define my_pread(A,B,C,D,E)		my_raid_pread(A,B,C,D,E)
#define my_chsize(A,B,C)		my_raid_chsize(A,B,C)
#define my_close(A,B)			my_raid_close(A,B)
#define my_tell(A,B)			my_raid_tell(A,B)
#define my_seek(A,B,C,D)		my_raid_seek(A,B,C,D)
#define my_lock(A,B,C,D,E)		my_raid_lock(A,B,C,D,E)
#define my_fstat(A,B,C)			my_raid_fstat(A,B,C)
#endif /* MAP_TO_USE_RAID */

#ifdef __cplusplus
extern "C" {
#endif

void init_raid(void);
void end_raid(void);

bool is_raid(File fd);
File my_raid_create(const char *FileName, int CreateFlags, int access_flags,
				uint raid_type, uint raid_chunks, ulong raid_chunksize,
				myf MyFlags);
File my_raid_open(const char *FileName, int Flags,
				uint raid_type, uint raid_chunks, ulong raid_chunksize,
				myf MyFlags);
int my_raid_rename(const char *from, const char *to, uint raid_chunks,
				myf MyFlags);
int my_raid_delete(const char *from, uint raid_chunks, myf MyFlags);
int my_raid_redel(const char *old_name, const char *new_name,
				uint raid_chunks, myf MyFlags);

my_off_t my_raid_seek(File fd, my_off_t pos, int whence, myf MyFlags);
my_off_t my_raid_tell(File fd, myf MyFlags);

uint my_raid_write(File,const byte *Buffer, uint Count, myf MyFlags);
uint my_raid_read(File Filedes, byte *Buffer, uint Count, myf MyFlags);

uint my_raid_pread(File Filedes, byte *Buffer, uint Count, my_off_t offset,
				myf MyFlags);
uint my_raid_pwrite(int Filedes, const byte *Buffer, uint Count,
				my_off_t offset, myf MyFlags);

int my_raid_lock(File,int locktype, my_off_t start, my_off_t length,
				myf MyFlags);
int my_raid_chsize(File fd, my_off_t newlength, myf MyFlags);
int my_raid_close(File, myf MyFlags);
int my_raid_fstat(int Filedes, struct stat *buf, myf MyFlags);

#ifdef __cplusplus
}

class RaidName {
	public:
		RaidName(const char *FileName);
		~RaidName();
		bool IsRaid();
		int Rename(const char * from, const char * to, myf MyFlags);
	private:
		uint _raid_type; /* RAID_TYPE_0 or RAID_TYPE_1 or RAID_TYPE_5 */
		uint _raid_chunks; /* 1..n */
		ulong _raid_chunksize; /* 1..n in bytes */
};

class RaidFd {
	public:
		RaidFd(uint raid_type, uint raid_chunks , ulong raid_chunksize);
		~RaidFd();
		File Create(const char *FileName, int CreateFlags, int access_flags,
		myf MyFlags);
		File Open(const char *FileName, int Flags, myf MyFlags);
		my_off_t Seek(my_off_t pos,int whence,myf MyFlags);
		my_off_t Tell(myf MyFlags);
		int Write(const byte *Buffer, uint Count, myf MyFlags);
		int Read(const byte *Buffer, uint Count, myf MyFlags);
		int Lock(int locktype, my_off_t start, my_off_t length, myf MyFlags);
		int Chsize(File fd, my_off_t newlength, myf MyFlags);
		int Fstat(int fd, MY_STAT *stat_area, myf MyFlags );
		int Close(myf MyFlags);
		static bool IsRaid(File fd);
		static DYNAMIC_ARRAY _raid_map;		/* Map of RaidFD* */
	private:

		uint _raid_type; /* RAID_TYPE_0 or RAID_TYPE_1 or RAID_TYPE_5 */
		uint _raid_chunks; /* 1..n */
		ulong _raid_chunksize; /* 1..n in bytes */

		ulong _total_block; /* We are operating with block no x (can be 0..many). */
		uint _this_block; /* can be 0.._raid_chunks */
		uint _remaining_bytes; /* Maximum bytes that can be written in this block */

		my_off_t _position;
		my_off_t _size; /* Cached file size for faster seek(SEEK_END) */
		File _fd;
		File *_fd_vector;		/* Array of File */
		off_t *_seek_vector;	/* Array of cached seek positions */

		inline void Calculate()
		{
			DBUG_ENTER("RaidFd::_Calculate");
			DBUG_PRINT("info",("_position: %lu _raid_chunksize: %d, _size: %lu",
				(ulong) _position, _raid_chunksize, (ulong) _size));

			_total_block = (ulong) (_position / _raid_chunksize);
			_this_block = _total_block % _raid_chunks; /* can be 0.._raid_chunks */
			_remaining_bytes = (uint) (_raid_chunksize - (_position - _total_block * _raid_chunksize));
			DBUG_PRINT("info",
				("_total_block: %d  this_block: %d  _remaining_bytes:%d",
				_total_block, _this_block, _remaining_bytes));
			DBUG_VOID_RETURN;
		}
};

#endif /* __cplusplus */
#endif /* USE_RAID */

